JP4348689B2 - Electronically controlled throttle device - Google Patents

Description

  The present invention opens and closes a throttle valve installed in an intake system of an engine for a vehicle by an electronic control system, and when an abnormality or failure has occurred in the electronic control system that makes it impossible to open or close the throttle valve. The present invention relates to an electronically controlled throttle valve device having means for preventing vehicle stoppage or runaway and for safety.

  In order to control the engine with high precision, instead of mechanically opening and closing the throttle valve by the driver's accelerator operation, a technology for opening and closing electronically using an electronic control system is widely known. The control system includes an actuator that opens and closes the throttle valve to a target opening position, and a control unit that sends a required drive signal to the actuator based on the accelerator operation amount and the throttle valve position.

  Here, when an abnormality or failure occurs in the control system, in order to avoid a situation where the vehicle becomes unable to run or runs away, a single step winding is used for an actuator that uses a stepping motor. When an abnormality occurs, another normal exciting winding is used to hold the throttle valve at a constant small opening (see Patent Document 1), and the control unit has an abnormality in the opening signal storage unit of the throttle valve. When it occurs, an alternative opening signal corresponding to the accelerator operation amount is calculated and output to the actuator, or when an abnormality occurs in the control unit or the actuator, the actuator is operated using the auxiliary control unit (see Patent Document 2) ), Has been proposed.

However, the former is a countermeasure means in a very specific case when an abnormality occurs in one of the two excitation windings of the stepping motor, and there is a concern that an accident cannot be avoided because it is fixed at a constant low speed. There is. On the other hand, the latter has an advantage that the opening / closing operation by electronic control can be continued and the vehicle can continue traveling at an arbitrary speed. This is a countermeasure for a case where the controllable degree is extremely limited. Therefore, it is not possible to cope with any abnormality of the control unit or the failure of the actuator that makes the opening / closing operation by electronic control of the throttle valve impossible. Furthermore, for example, when a mechanical element such as an actuator bearing or a reduction gear is damaged, the throttle valve is fixed at the opening position at the time of occurrence of the damage. It is impossible to handle with things.
Japanese Patent Laid-Open No. 6-213012 JP-A-6-137206

  The present invention has been made in order to solve the above-described problems, and when the electronic control system becomes abnormal or malfunctions, the throttle valve cannot be electronically opened and closed. It is an object of the present invention to provide an electronically controlled throttle valve device having means capable of opening and closing mechanically and allowing a vehicle to travel safely.

  The present invention includes a control unit and an actuator, and an electronically controlled throttle device in which the actuator is operated to open and close the throttle valve to a target opening position according to a command issued by the control unit in accordance with a driver's accelerator operation amount. The above-mentioned problems were solved by doing the following.

  That is, the electronically controlled throttle valve device according to the present invention is an actuator that operates according to a command corresponding to the accelerator operation amount output from the control unit, an actuator lever that can freely rotate on the throttle valve shaft, an integral rotation on the throttle valve shaft, and an axial movement. An electronic opening / closing means for transmitting and closing the throttle valve shaft by transmitting the rotation of the actuator to the throttle valve shaft via the actuator lever and the throttle valve shaft lever; and having an auxiliary actuator, the actuator lever and the throttle valve A separation mechanism for releasing the linkage with the shaft lever and a switching means including an operation mechanism for mechanically opening and closing the throttle valve are provided. When the switching means has an abnormality or failure in the electronic control system including the control unit and the actuator, the separation mechanism releases the interlock between the actuator lever and the throttle valve shaft lever by operating the auxiliary actuator. The operation mechanism opens and closes the throttle valve according to the operation amount of the auxiliary actuator.

  Examples of abnormalities and failures in the electronic control system include control unit abnormalities or failures that make the actuator uncontrollable, and failures such as disconnection or seizure of the actuator. Open / close control becomes impossible. Secondly, breakage of mechanical elements such as actuator bearings and reduction gears is exemplified. In such a case, the throttle valve is fixed at the opening position at the time of breakage and cannot be opened and closed, so that the vehicle may run away.

  These abnormalities and failures can be easily known by appropriately using or applying well-known abnormality detection, failure diagnosis, fail safe, and abnormality occurrence notification means. Further, the operation of the auxiliary actuator of the switching means is performed automatically when the control unit issues a command when the occurrence of the abnormality or failure is detected, or artificially when the driver receives a command and issues the command. Can be done.

  In the electronically controlled throttle valve device according to the present invention, when the electronic control system is normal, the actuator lever and the throttle valve shaft lever are coupled to open and close the throttle valve electronically by the actuator. When an abnormality or failure occurs in the system, the throttle valve shaft lever is separated from the actuator lever by operating the auxiliary actuator, and then the throttle valve shaft is rotated via the throttle valve shaft lever to mechanically open and close the throttle valve. The throttle valve is separated from the electronic control system and can be mechanically opened and closed by a single operation of operating the auxiliary actuator.

  In one embodiment of the present invention, the switching means is free to rotate on the throttle valve shaft and is rotated by the auxiliary actuator, and is movable in the axial direction integrally with the throttle valve shaft and cannot be rotated. The auxiliary actuator includes a driven member. The auxiliary actuator first rotates the rotating member to move the driven member and the throttle valve shaft lever in the axial direction, thereby separating the throttle valve shaft lever from the actuator lever. The throttle valve is opened and closed by rotating. Also, when the throttle valve shaft lever is disconnected from the actuator lever, the throttle valve return spring brings the throttle valve to the closed position, and then the throttle valve shaft lever is rotated from the phase at the throttle valve open position to open the throttle valve. It is supposed to be In addition, an intermediate lever is provided between the auxiliary actuator, the rotating member, and the throttle valve shaft lever. The intermediate lever rotates the rotating member at the early stage of operation of the auxiliary actuator to separate the throttle valve shaft lever from the actuator lever, and the latter stage of operation. The throttle valve shaft lever is rotated to open and close the throttle valve. Accordingly, it is possible to smoothly switch from the electronic opening / closing operation of the throttle valve to the mechanical opening / closing operation.

  In another embodiment of the present invention, the maximum opening position of the throttle valve by the rotation of the throttle valve shaft lever is adjustable between the fully open position and the small opening degree. Thereby, driving | running | working of a vehicle can be safely continued within the set maximum speed.

  As described above, according to the present invention, when an abnormality or failure that makes it impossible to open or close the throttle valve occurs in the electronic control system, the throttle valve can be operated by a single operation that activates the auxiliary actuator regardless of the occurrence location. Can be separated from the electronic control system and switched to a mechanical opening / closing operation to allow the vehicle to travel safely.

  An embodiment of the present invention will be described below with reference to the drawings. A throttle valve lever 5 is attached to one end of a throttle valve shaft 3 that is rotatably supported by a throttle body 1 across an intake passage 2. A throttle valve return spring 6 comprising a torsion coil spring engages with the throttle valve lever 5 to urge the throttle valve shaft 3 to rotate in the direction to close the throttle valve 4. A throttle valve position sensor 7 is provided at the shaft end of the throttle valve shaft 3.

  At the other end of the throttle valve shaft 3, an actuator lever 14 and a rotary member 21 are rotatably fitted and supported, and the throttle valve shaft lever 16 is fitted together by a key coupling portion 17 so as to rotate integrally and move in the axial direction. It is disguised. Further, a driven member 22 is attached to the throttle valve shaft lever 16 so as to face the rotating member 21, and the driven member 22 is made non-rotatable by inserting a detent pin 23 installed in the throttle body 1.

  The actuator 8 and the auxiliary actuator 25 are installed on a mounting base (not shown) provided at an appropriate place around the throttle body 1 or the engine. The actuator 8 is a DC motor, and the control unit 11 outputs based on the accelerator operation amount detected by the accelerator position sensor 10 that detects the depression amount of the accelerator pedal 9 and the throttle valve position detected by the throttle valve position sensor 7. The throttle valve 4 is opened / closed to a target opening position by a drive signal, and these constitute a well-known electronic control system.

  The rotation of the actuator 8 is transmitted to the driving lever 13 through the reduction gear 12, and is transmitted to the actuator lever 14 via a link member 15 having an adjustable length in which both ends of the driving lever 13 and the actuator lever 14 are freely coupled to each other. It is done. The actuator lever 14 and the throttle valve shaft lever 16 are provided with engaging protrusions 14A and 16A formed by bending. These are adjacent to each other, and when the actuator lever 14 is rotated by the actuator 8 and the projection 14A pushes the projection 16A, the throttle valve shaft lever 16 is rotated and the throttle valve 4 is operated in the opening direction. Further, the throttle valve shaft lever 16 is rotated integrally with the throttle valve shaft 3 by the throttle valve return spring 6 to cause the throttle valve 4 to operate in the closing direction, and the projection 16A pushes the projection 14A to return the actuator 8 to the initial position. .

  The electronic valve opening / closing operation of the throttle valve 4 is performed as described above, and the actuator 8, the control unit 11, the actuator lever 14, and the throttle valve shaft lever 16 constitute an electronic opening / closing means A.

  Next, the rotating member 21 and the driven member 22 have mountain-shaped cams 21A and 22A facing each other on a circle centering on the throttle valve shaft 3, and these cams 21A and 22A overlap each other. Yes. Further, the throttle valve shaft lever 16 is provided with a pressing spring 24 that acts in the direction of overlapping the protrusion 16A adjacent to the protrusion 14A.

  The auxiliary actuator 25 is a fluid pressure cylinder, and the tip of a piston rod 28 extending from the piston 27 is coupled to an intermediate lever 32 rotatably fitted to a support shaft 31 projecting from the throttle body 1 via an auxiliary stub 33. ing. A piston spring 29 is caused to act on the piston rod 28 side in the cylinder block 26, and a working fluid supply / discharge passage 34 is connected to the cylinder chamber 30 on the opposite side. The supply / discharge passage 34 is connected to either the pressure source 36 or the drain 37 by a direction switching valve 35 which is a working fluid supply / discharge means, and the piston 27 is connected to the piston rod by feeding the working fluid of the pressure source 36 into the cylinder chamber 30. The piston 27 moves in the direction of pushing out the piston rod 28 by discharging the working fluid. As a result, the intermediate lever 32 reciprocates within a certain angle range.

  The intermediate lever 32 and the rotating member 21 are coupled to each other by a link member 38 having both ends rotatably coupled thereto, and the intermediate lever 32 is formed of a screw rod facing the throttle valve shaft lever 16 to adjust the protrusion length. The pushing member 39 is provided.

  The auxiliary actuator 25, the intermediate lever 32, the link member 38, the rotating member 21, and the driven member 22 described above constitute a separating mechanism B1 that releases the interlocking between the actuator lever 14 and the throttle valve shaft lever 16. The auxiliary actuator 25, the intermediate lever 32, the push member 39, and the throttle valve shaft lever 16 constitute an operation mechanism B2 that mechanically opens and closes the throttle valve 4, and the separation mechanism B1 and the operation mechanism B2 are the throttle valve 4 respectively. The switching means B is configured to switch from the electronic opening / closing operation to the mechanical opening / closing operation.

  In this embodiment having such a configuration, when the electronic control system is normal, the rotation of the actuator 8 driven by the drive signal output from the control unit 11 is made to reduce the reduction gear 12, the driving lever 13, and the link member 15. Then, it is transmitted to the actuator lever 14 and the throttle valve shaft lever 16 is pushed by the actuator lever 14 to cause the throttle valve 4 to operate in the opening direction, and the throttle valve return spring 6 causes the throttle valve 4 to operate in the closing direction. The throttle valve shaft lever 16 pushes the actuator lever 14 to return the actuator 8 to the initial position.

  2 shows the state when the throttle valve 4 is in the fully closed position, that is, the idle opening position, and FIG. 3 shows the state when the throttle valve 4 is in the fully open position. The actuator lever 14 and the throttle valve shaft lever 16 are shown. And the rotating member 21 are stopped.

  When an abnormality or failure occurs in the electronic control system and the throttle valve 4 becomes uncontrollable or fixed at a certain opening position, the control unit 11 detects them and switches to a mechanical opening / closing operation. This switching is automatically performed or manually performed by the driver who has been notified of the occurrence of an abnormality, and is switched by a single operation of operating the auxiliary actuator 25 and then the opening / closing operation of the throttle valve 4. Is done.

  That is, by operating the direction switching valve 35 to introduce the working fluid of the pressure source 36 into the cylinder chamber 30, the piston 27 rotates the intermediate lever 32 via the piston rod 28 and the auxiliary rod 33, and the intermediate lever 32 The rotating member 21 is rotated via the link member 38. Accordingly, the cam 21A pushes the cam 22A and compresses the push spring 24 to move the driven member 22 in the axial direction of the throttle valve shaft 3, and the protrusion 16A of the throttle valve shaft lever 16 and the actuator lever 14 that move integrally therewith. The engagement with the projection 14A is released, and the throttle valve shaft lever 16 is disconnected from the actuator lever 14.

  At this time, the throttle valve 4 is returned to the fully closed position by the throttle valve return spring 6 regardless of the phase of the throttle valve shaft lever 16. On the other hand, the piston 27 of the auxiliary actuator 25 is in the middle of a stroke, and by continuously feeding the working fluid into the cylinder chamber 30, the intermediate lever 32 further rotates and the push member 39 protrudes from the throttle valve shaft lever 16. 16A is pushed and the throttle valve 4 is operated in the opening direction. In the present embodiment, the throttle valve 4 is opened to a small opening when the piston 27 is stroked to the maximum, and the vehicle is driven at a low speed, so that the rotating member 21 starts to open the throttle valve 4 of the piston 27. The cams 21 </ b> A and 22 </ b> A are formed so that the throttle valve shaft lever 16 is disconnected from the actuator lever 14 while being rotated to the end of opening.

  FIG. 4 shows a state when the throttle valve shaft lever 16 is disconnected from the actuator lever 14. In this state, when the throttle valve 4 is at the fully closed position and at the set maximum opening position, FIG. 5 and FIG. Respectively. By operating the direction switching valve 35 to adjust the discharge amount of the working fluid from the cylinder chamber 30 or the feed amount of the working fluid into the cylinder chamber 30, the throttle valve 4 is moved between FIG. 5 and FIG. 6. With an arbitrary opening, the vehicle can be driven at an arbitrary low speed.

  FIG. 7 shows a different embodiment of the separation mechanism B1 for releasing the interlocking between the actuator lever 14 and the throttle valve shaft lever 16, and a rotating member 21B made of a roller or a ball is provided on the rotating member 21, and a driven member is provided. 22 is brought into contact with the rolling member 21B, and as the rotating member 21 rotates, the rolling member 21B pushes the cam 22B to move the driven member 22 and the throttle valve shaft lever 16 in the axial direction of the throttle valve shaft 3. The protrusions 14A and 16A are separated.

  According to this embodiment, there is an advantage that when the rotating member 21 is rotated, the driven member 22 can be pushed and moved with a small frictional resistance. The same applies when the rolling member 21B is installed on the driven member 22 and the cam is installed on the rotating member 21.

  As the working fluid pressure source 35 for operating the auxiliary actuator 25, which is a fluid pressure cylinder in the embodiment described with reference to FIGS. 1 to 6, the pressure is generated by vehicle brake pressure air, engine lubricating oil, and a separately prepared pump. Pressure air or pressure oil is exemplified and either of these is used.

  In the present invention, the auxiliary actuator is not limited to the fluid pressure cylinder, and an electric motor can be used. That is, when a linear motor is used as the electric motor, the movable element is replaced with the piston rod 28 or the movable element is coupled to the piston rod 28. When a rotary motor capable of forward / reverse rotation is used as the electric motor, the output shaft 42 of the auxiliary actuator 41, which is a rotary motor, is splined to a screw rod 43 that is screwed into a cylinder block 46 as shown in FIG. And the like, and the tip of the screw rod 43 is brought into contact with the piston 47 so that the piston 48 is separated from the actuator lever 14 and the throttle valve shaft lever 16 through the intermediate lever 32 and the throttle valve when the rotary motor rotates forward. 4 is opened, and the piston spring 49 closes the throttle valve 4 during reverse rotation. Alternatively, as shown in FIG. 8B, the cam 44 is fixed to the output shaft 42 and brought into contact with the piston 47, and the cam 44 pushes the piston 47 during the forward rotation of the auxiliary actuator 41, which is a rotary motor, so It is assumed that the valve shaft lever 16 is disconnected and the throttle valve 4 is opened, and the piston spring 49 causes the throttle valve 4 to be closed during reverse rotation.

  Alternatively, the actuator lever 14 and the throttle valve shaft lever can also be operated by the driver manually operating any one of the intermediate lever 32, the link member 38, and the rotating member 21 without using the auxiliary actuators 25 and 41 as described above. 16 and the throttle valve 4 can be opened and closed. In this case, it is advantageous for facilitating manual operation to expose each member to a place where it can be easily operated in the driver's seat, or to provide a lever or handle that can be held in the hand in the driver's seat. is there.

  In the present embodiment, the mechanical opening / closing operation of the throttle valve 4 is performed within a small opening, but the shape of the cams 21A, 22A, 22B, the maximum stroke or the maximum rotation speed of the auxiliary actuators 25, 41 are used. Can be arbitrarily set, and for example, an opening / closing operation can be arbitrarily performed between the valve closing position and the fully opened position. Further, when the throttle valve 4 is opened and closed by the auxiliary actuators 25 and 41, the supply / discharge of the working fluid to and from the fluid pressure cylinder by the direction switching valve 35 is controlled by the driver's manual operation, or the forward direction of the electric motor or By controlling the reverse stroke and the number of rotations, an arbitrary opening, that is, the vehicle can be set to an arbitrary traveling speed. Alternatively, the throttle valve 4 can be set to an arbitrary opening degree by operating the auxiliary actuators 25 and 41 according to the signal of the accelerator position sensor 10 that detects the depression amount of the accelerator pedal 9 of the driver.

The longitudinal cross-sectional view when the electronic control which shows embodiment of this invention is performed. The figure explaining the positional relationship of each lever of FIG. 1 in a throttle valve fully closed position. The figure explaining the positional relationship of each lever of FIG. 1 in a throttle valve full open position. FIG. 2 is a longitudinal sectional partial view when the throttle valve is mechanically opened and closed in the embodiment of FIG. 1. The figure explaining the positional relationship of each lever of FIG. 4 in a throttle valve fully closed position. The figure explaining the positional relationship of each lever of FIG. 4 in the throttle valve setting maximum opening position. The front fragmentary figure which shows embodiment from which a separation mechanism differs. The longitudinal cross-sectional view which shows different embodiment of an auxiliary actuator.

Explanation of symbols

3 throttle valve shaft, 4 throttle valve, 8 actuator, 9 accelerator pedal, 10 accelerator position sensor, 11 control unit, 14 actuator lever, 16 throttle valve shaft lever, 21 rotating member, 22 driven member, 25, 41 auxiliary actuator, A Electronic switching means, B switching means, B1 separation mechanism, B2 operation mechanism

Claims (5)

An actuator that operates according to a command corresponding to the accelerator operation amount output by the control unit, an actuator lever that can freely rotate on the throttle valve shaft, and a throttle valve shaft lever that rotates integrally with the throttle valve shaft and is movable in the axial direction. Electronic opening / closing means for transmitting rotation to the throttle valve shaft via the actuator lever and throttle valve shaft lever to move the throttle valve open and close;
A rotating member that has an auxiliary actuator and includes a separation mechanism that releases the interlocking between the actuator lever and the throttle valve shaft lever, and an operation mechanism that mechanically opens and closes the throttle valve, and is rotatable on the throttle valve shaft And a driven member that is axially movable and non-rotatable integrally with the throttle valve shaft lever, and the auxiliary actuator first rotates the rotating member to connect the driven member and the throttle valve shaft lever. Switching means for separating the throttle valve shaft lever from the actuator lever by moving in the axial direction, and then rotating the throttle valve shaft lever to open and close the throttle valve ;
The switching means operates the auxiliary actuator when an abnormality or failure occurs in the electronic control system including the control unit and the actuator, whereby the separation mechanism links the actuator lever and the throttle valve shaft lever. And then the operation mechanism opens and closes the throttle valve according to the operation amount of the auxiliary actuator.
An electronically controlled throttle valve device characterized by that. When the throttle valve shaft lever is disconnected from the actuator lever, the throttle valve return spring brings the throttle valve to the closed position, and then the throttle valve shaft lever is rotated from the phase at the throttle valve closed position to The electronically controlled throttle valve device according to claim 1, wherein the electronically controlled throttle valve device is opened. An intermediate lever is provided between the auxiliary actuator, the rotating member, and the throttle valve shaft lever, and the intermediate lever rotates the rotating member in the first stage of operation of the auxiliary actuator to separate the throttle valve shaft lever from the actuator lever. The electronically controlled throttle valve device according to claim 1 or 2, wherein the throttle valve shaft lever is rotated at a later stage of operation to open and close the throttle valve. The maximum opening position of the mechanical opening / closing operation of the throttle valve by the rotation of the throttle valve shaft lever is arbitrarily set between a full opening and a small opening degree. Electronically controlled throttle device. The separation mechanism releases the interlock between the actuator lever and the throttle valve shaft lever, and the operation mechanism subsequently opens and closes the throttle valve by manual operation instead of the auxiliary actuator. The electronically controlled throttle valve device according to claim 1, 2, 3, or 4.

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